As uplink and downlink services in a communications system are increasingly asymmetric, and a ratio of uplink services to downlink services constantly changes with time, use of fixed paired spectrums and a fixed uplink-downlink timeslot configuration already cannot effectively support dynamic asymmetries of services; in addition, due to explosive growth of a total volume of uplink and downlink services, a half duplex mode already cannot satisfy requirements in some scenarios, and full duplex becomes a possible potential technology. Flexible full duplex fully considers growth of the total service volume and asymmetries, and can adaptively allocate uplink and downlink resources according to distribution of uplink and downlink services, and effectively improve utilization of system resources to satisfy requirements in a future network.
In a flexible frequency band technology, some uplink frequency bands in a frequency division duplex (English: Frequency Division Duplex, FDD for short) system are configured as flexible frequency bands. In an actual application, according to distribution of uplink and downlink services in a network, flexible frequency bands are allocated for uplink transmission or downlink transmission, so that uplink and downlink spectrum resources match uplink and downlink service requirements, thereby improving spectrum utilization. As shown in FIG. 1, when a downlink service volume in a network is higher than an uplink service volume, the network may configure a frequency band f4 that is originally used for uplink transmission as a frequency band used for downlink transmission. In a flexible full duplex technology, time division duplex (English: Time Division Duplex, TDD for short) may be used in the frequency band f4 to perform uplink and downlink service transmission. In a Long Term Evolution (English: Long Term Evolution, LTE for short) system, there are seven different subframe configuration modes in total in time division duplex (English: Time Division Duplex, TDD for short) uplink-downlink configurations. When neighboring cells use different TDD configurations, for flexible FDD full duplex, cross-timeslot interference may be caused between neighboring cells when some uplink (English: uplink, UL for short) frequency bands are configured as downlink (English: Downlink, DL for short) frequency bands according to service requirements.
In the current 3rd Generation Partnership Project (English: 3rd Generation Partnership Project, 3GPP for short), the following mode is used for power control on a physical uplink shared channel (English: Physical Uplink Shared Channel, PUSCH for short):
                    P                  PUSCH          ,          c                    ⁡              (        i        )              =          min      ⁢              {                                                                                                  P                                          CMAX                      ,                      c                                                        ⁡                                      (                    i                    )                                                  ,                                                                                                          10                  ⁢                                                            log                      10                                        ⁡                                          (                                                                        M                                                      PUSCH                            ,                            c                                                                          ⁡                                                  (                          i                          )                                                                    )                                                                      +                                                      P                                          O_PUSCH                      ,                      c                                                        ⁡                                      (                    j                    )                                                  +                                                                                                                                                    α                      c                                        ⁡                                          (                      j                      )                                                        ·                                      PL                    c                                                  +                                                      Δ                                          TF                      ,                      c                                                        ⁡                                      (                    i                    )                                                  +                                                      f                    c                                    ⁡                                      (                    i                    )                                                                                      }              ,
where PCMAX,c(i) indicates a maximum power, MPUSCH,c(i) indicates a quantity of physical resource blocks (English: Physical Resource Block, PRB for short), PO_PUSCH,c(j) and αc(j) are semi-statically configured parameters, PLc is a path loss estimated by user equipment (English: User Equipment, UE for short), ΔTF,c(i) is an incremental value for different modulation and coding schemes (English: Modulation and Coding Scheme, MCS for short), and fc(i) is a power adjustment value formed by closed-loop power control of a terminal.
When a base station delivers a transmit power control (English: Transmit Power Control, TPC for short) command, there are the following two modes: One is an accumulated mode (English: accumulated mode), the other is an absolute mode (English: absolute mode). The accumulated mode is to increase or decrease progressively to make a change. Changing a transmit power by using a TPC command in the accumulated mode is a slow process, and it is impossible to jump to different interference levels between a flexible subframe and a fixed subframe. The absolute mode is to make a change in a single attempt. The transmit power may be adjusted in a larger range by using a TPC command in the absolute mode. However, in the absolute mode, because an adjusted transmit power cannot be accumulated, a total adjusted power is relatively low. In addition, the absolute mode is not available for power control on a physical uplink control channel (English: Physical Uplink Control Channel, PUCCH for short).
In the foregoing PUSCH power control, PO_PUSCH,c(j) and αc(j) are semi-statically configured. A semi-static configuration means that a configuration period is relatively long, and that a value remains unchanged for all subframes. The semi-static configuration is not a dynamic configuration (which has a very short configuration period and occurs very frequently). According to a configured power control mode (accumulated mode or absolute mode), a TPC command related to fc(i) may adjust the transmit power of the UE within a predefined range. A range of adjustment by the TPC command in the accumulated mode is relatively small, but the adjusted transmit power may be accumulated, and finally, the range may be relatively large.
In an ultra dense network (English: Ultra Dense Network, UDN for short) using flexible full duplex, a main feature of the UDN is: a radius of a typical cell is far less than that of a macro cell, a quantity of UEs connected to each small cell is not large, and network planning and optimization are not considered for deployment of the UDN network. Therefore, uplink-downlink cross-timeslot interference is an obstacle in deploying a flexible full duplex network. In a UDN scenario, interference does not occur merely between neighboring cell clusters, but severer interference occurs between neighboring small cells. In an application scenario in which a flexible full duplex network of an FDD system is deployed, power control needs to be redesigned for UE, because interference levels of different subframes become very complex.
In the prior art, a power control parameter is configured in a semi-static mode, and its value remains unchanged for all subframes. However, if there is cross-timeslot interference between neighboring cells, interference between different uplink subframes may vary. Using a cell as an example, interference received in an uplink subframe by the cell may be uplink interference from a neighboring base station, but interference received in another uplink subframe may be downlink interference from UE within coverage of a neighboring base station. In the foregoing case, if the base station still uses the unified semi-static configuration mode to perform power control, interference differences between different downlink subframes are ignored. When data is transmitted according to such power control, cross-timeslot interference affects effective transmission of data, and reduces an effective transmission rate of data.